[login] split authentication logic from post authentication logic (closes #2200755)
* The Session manager is now only in charge of providing a valid session.
* LoginControllers are now used in all case but wrong credential.
* The LoginControllers are in charge of redirecting the user to the page wanted
to see in the first place, expected to see.
* The login form is now always submitted to the login controller with an extra
argument pointing to the url we should redirect too after successful
authentication.
The ``"log out first logic"`` logic on login controller is removed because:
1. Other web actor do not do that.
2. Removed code do not need to be reimplemented.
3. We can only get it to work again in a single case: use do a GET request on
http://www.my-cw-stuff.io/login
4. I do not see it's purpose.
#! /bin/sh -e
if [ -x "/etc/init.d/cubicweb-ctl" ]; then
invoke-rc.d cubicweb-ctl restart || true
fi
#DEBHELPER#
exit 0